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101.
周长水 《安徽电子信息职业技术学院学报》2004,3(4):20-22
随着中专生源的变化,中专语文因材施教势在必行。而因材施教绝不仅仅是技术层面上的问 题,而是内涵丰富。要求教师以人为本,用“心”教学,与时俱进。具体在情感态度、方式方法等方面要做到八 有:爱材之情;超材之能;识材之方;激材之术;练材之法;容材之量;管材之胆;育材之道。 相似文献
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Results of a series of experimental tests performed to determine the influence of matrix characteristics on the leaching mechanism
of copper aluminum oxychloride immobilized into cement matrices are presented. The objective of this work was to investigate
the leaching mechanism of copper as a constituent of copper aluminum oxychloride (‘CAOX’). Transport phenomena involved in
the leaching of a waste material from a composite matrix into surrounding water were investigated using three methods based
on theoretical equations: (i) diffusion equation derived for a plane source model, (ii) rate equation for diffusion coupled
with a first-order reaction and (iii) the leaching data were also analysed by an empirical method employing a polynomial equation.
These three methods are compared with respect to their applicability to the leaching data. 相似文献
106.
永平铜矿低品位氧化矿堆浸技术的改进 总被引:5,自引:0,他引:5
分析了永平铜矿低品位氧化矿堆浸生产过程中存在的技术问题及问题产生的原因,考察了矿堆容重的改变及不同矿堆高度对溶液渗透速度的影响。详细介绍了对堆浸技术所进行的改进:(1)将原来前进式筑堆改为后退式筑堆;(2)在矿堆底部增加排水层;(3)变常规高层堆浸为硫酸熟化预处理薄层浸出;(4)实施分区喷淋与休闲轮换作业的布液制度。技术改进后,堆浸生产技术指标大为改观,取得了明显的经济效益。 相似文献
107.
通过排水采集器模拟试验,研究了太湖地区不同施肥水平下,麦作期间农田氮素淋洗特点。结果表明,麦季氮素渗漏损失以NO3--N为主,占总氮量的36.2%~99.1%,平均高达82.9%,NO3--N淋洗量随施肥量的增加而增加。不同施肥水平及肥料种类,对于NO3--N淋洗有着不同的影响,在试验的施肥水平下,麦作期间氮素淋失对地下水存在潜在污染。 相似文献
108.
K. SARVESWARA RAO R. P. DAS H. S. RAY 《Mineral Processing and Extractive Metallurgy Review》2013,34(3-4):209-233
The leaching of a real multimetal bulk concentrate cannot often be adequately understood on the basis of published literature on simpler and often ideal systems because the process is far too complex, Moreover, the data can become ambiguous in the absence of adequate information on raw materials. Thus any process development work requires a thorough knowledge of the raw material characteristics. This paper describes the use of an interdisciplinary study for a better understanding of ammonia leaching of multimetal sulphides. The techniques employed comprise of X-ray diffraction, thermal analysis, chemical analysis and microscopy. 相似文献
109.
Valuable metal extraction technology from thermal power plant fly ash is limited. In the present study, aluminium is extracted from fly ash as highly pure aluminium sulphate (>99.0%) by leaching with sulphuric acid, followed by pre-concentration and successive crystallization. Two types of fly ashes from different sources, i.e., Talcher Thermal Power Station (TTPS) and Vedanta Aluminium Company Limited (VAL) were chosen for comparative study on the extraction of aluminium as aluminium sulphate. The product is characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Purity of aluminium sulphate was also investigated by inductively coupled plasma–optical emission spectrometry (ICP–OES). The extraction efficiency of aluminium depends on the varied solid-to-liquid ratio (fly ash : 18 mol/L H2SO4, g/mL) and particle size of fly ashes. Physico-chemical analysis indicates that the obtained product is Al2(SO4)3·18H2O, having low iron content (0.08%). 相似文献
110.
Primary beneficiation was successfully performed prior to dissolution of manganotantalite (sample A) and ferrotantalite (sample C) samples obtained from two different mines in the Naquissupa area, Mozambique. Magnetic separation removed the majority of iron and titanium, whereas H2SO4 leaching removed a large portion of thorium and uranium in these samples. Analytical results indicated that 64.14wt% and 72.04wt% of the total Fe and Ti, respectively, and -2wt% each of Nb205 and Ta205 were removed from sample C (ferrotantalite) using the magnetic separation method, whereas only 9.64wt% and 8.66wt% of total Fe203 and TiO2, respectively, and -2wt% each of NbEOs and Ta2O5 were removed from sample A (manganotantalite). A temperature of 50℃ and a leaching time of 3 h in the presence of concentrated HESOa were observed to be the most appropriate leaching conditions for removal of radioactive elements from the tantalite ores. The results obtained for sample A under these conditions indicated that 64.14wt% U3O8 and 60.77wt% ThO2 were leached into the acidic solution, along with 4.45wt% and 0.99wt% of Nb2O5 and Ta2O5, respectively. 相似文献